1. Field of the Invention
The present invention relates to a semiconductor device having a temperature detection function.
2. Description of the Background Art
Recently, semiconductor technology is miniaturized in order to implement further high speed and high integration of a semiconductor integrated circuit. Accordingly, an effect that a temperature variation has on device characteristics becomes apparent, and it is necessary to appropriately control the characteristics according to the temperature so that the device may not be erroneously operated by the temperature variation. Thus, it is necessary to correctly detect a temperature of the device, and various kinds of temperature detection circuits have been proposed conventionally. For example, Japanese Patent Application Laid-Open Nos. 2000-55742, 58-35431 (1983), 05-307882 (1993), 09-223395 (1997), 2000-269417 and 10-239097 (1998) disclose a temperature detection circuit which detects a temperature of a semiconductor device based on a variation of a frequency of a clock signal with temperature.
However, sufficient temperature detection precision cannot be provided in the conventional temperature detection circuit, so that an erroneous operation of the device due to a temperature variation could not be completely prevented.
Meanwhile, since the characteristics of the device is varied due to a variation in manufacturing process, when the characteristics of the device is adjusted based on a temperature detection result, it is important to note that they are not affected by the variation in manufacturing process.